title: Impact of folate intake on prostate cancer recurrence following definitive therapy: data from CaPSURE™.
abstract: OBJECTIVE
  A randomized, placebo controlled clinical trial of folic acid supplementation for the chemoprevention of colorectal adenoma revealed an increased incidence of prostate cancer in the treatment group. Limited data exist on postdiagnostic folate/folic acid intake and the risk of prostate cancer progression. We prospectively examined the association between postdiagnostic folate consumption and the risk of prostate cancer recurrence after radical prostatectomy, external beam radiation therapy and brachytherapy.
  
  
  METHODS
  This study was done in 1,153 men treated with radical prostatectomy, external beam radiation therapy and brachytherapy who had clinical stage T1-T2c prostate adenocarcinoma and participated in the CaPSURE Diet and Lifestyle substudy by completing the semiquantitative Food Frequency Questionnaire in 2004 to 2005. We used Cox proportional hazards regression to analyze the association between folate intake and prostate cancer progression.
  
  
  RESULTS
  Prostate cancer progressed in 101 men (8.76%) during a mean 34-month followup. After multivariate adjustment we observed no evidence of an association of the intake of total folate, dietary folate or dietary folate equivalents with prostate cancer recurrence. On secondary analysis by treatment after radical prostatectomy patients in the lowest decile of dietary folate intake had a 2.6-fold increase in the risk of recurrence (HR 2.56, 95% CI 1.23-5.29, p = 0.01). In patients treated with external beam radiation and brachytherapy we observed no evidence of an association between prostate cancer progression and increased folate intake.
  
  
  CONCLUSIONS
  Results suggest that the consumption of foods and multivitamins that contain folate is not associated with prostate cancer progression after definitive treatment.
authors.affiliation: Division of Urologic Oncology, Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania. Electronic address: tomaszewski.jeffrey@gmail.com.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Tomaszewski
authors.affiliation: Department of Epidemiology and Biostatistics, University of California-San Francisco, San Francisco, California.
authors.forename: Erin L
authors.initials: EL
authors.lastname: Richman
authors.affiliation: Department of Urology, University of California-San Francisco, San Francisco, California.
authors.forename: Natalia
authors.initials: N
authors.lastname: Sadetsky
authors.affiliation: Division of Urologic Oncology, Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Denise S
authors.initials: DS
authors.lastname: O'Keefe
authors.affiliation: Department of Urology, University of California-San Francisco, San Francisco, California.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Carroll
authors.affiliation: Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Davies
authors.affiliation: Department of Epidemiology and Biostatistics, University of California-San Francisco, San Francisco, California; Department of Urology, University of California-San Francisco, San Francisco, California.
authors.forename: June M
authors.initials: JM
authors.lastname: Chan
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology* / Q000517:prevention & control* / Q000628:therapy; D000368:Aged; D005492:Folic Acid / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology* / Q000517:prevention & control*; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000517:prevention & control* / Q000628:therapy
chemical_list: D005492:Folic Acid
keywords: disease progression; folic acid; local; neoplasm recurrence; prostate; prostatic neoplasms